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71.
72.
Effect of paclobutrazol onin vitro formation of potato microtubers and their sprouting after storage
I. Šimko 《Biologia Plantarum》1994,36(1):15-20
Paclobutrazol, the gibberellin biosynthesis inhibitor, acceleratedin vitro tuber initiation of potato cv. Rema and increased the uniformity of tuberization period. However, the high concentrations (10–1000 mg l?1) of this retardant, strongly decreased mass and/or number of microtubers. The microtubers were harvested and stored in darkness (22±2°C) for 250 d. After this period both sprouting and growth of sprouts were affected by previous paclobutrazol treatment. 相似文献
73.
Photosynthesis inhibition in algae (Chlorella) and plant (spinach) chloroplasts by quaternary ammonium salts of heptacaine {N-[2-(2-heptyloxyphenylcarbamoyloxy)-ethyl]-N-alkylpiperidinium
bromides} depended on the alkyl chain length of the alkyl substituent and showed good correlations with theoretical hydrophobic
fragment constants as well as with experimentally determined physico-chemical parameters, namely extraction constants and
surface activities.
Communicated by. Z. ŠESTáK 相似文献
74.
Exploratory data analysis based on multivariate statistical analysis techniques was introduced as a new approach to expressing
the toxicity of chemical substances at the simultaneous acceptance of various cell models. Using principal component analysis
and cluster analysis methods the toxicity of chlorinated phenol derivatives on employing some of the cell models (chlorococcal
algae, cyanobacteria, bacteria, micromycetes, plant and animal cells) was characterized. The previous empirical experience
that the toxicity of chlorinated phenol derivatives will increase with a growing degree of chlorination and that the presence
of the methoxy group will cause a lowering of the toxic effect was demonstrated. The relationship between groups of tests
used was presented. 相似文献
75.
76.
Summary
Mortierella alpina S-17 cultivated in shaker flasks in the semisynthetic liquid medium with 3% glucose at 28 °C for 14 days accumulated 2.1 g/l of intracellular lipid rich in arachidonic acid (ARA). The content of ARA was 50 % of the total fatty acids. The simple method for high pure methyl arachidonate preparation was developed. 相似文献
77.
Summary Flow microcalorimeter was used for the study of microkinetic properties of Escherichia coli cells enriched with the penicillin G acylase activity immobilized in calcium pectate gel. The experimental kinetic data were obtained by measurement of the thermometric signal in the microcalorimetric column with immobilized enzyme and described by the introduced mathematical model involving the mass transfer and reaction kinetic phenomena. 相似文献
78.
A total of 27 fragile X pedigrees consisting of over 100 nuclear families were analyzed by Southern blotting methods and probes StB12.3 and StB12.3xx to detect the expansion of the (CGG)
n
repeat within the FMR-1 gene and the abnormal methylation pattern of the adjacent DNA region responsible for the fragile X syndrome. Clinical expression was found to be associated with the presence of a full mutation ( > 500 bp, associated with abnormal methylation) in all the males and 50% of the females studied, whereas individuals carrying a premutation ( = 100–700 bp) were normal. A preferential size increase in the enlarged (CGG)
n
repeat was detected in successive generations, the instability being stronger when transmitted from a female than from a male. No expansion of the premutation to the full mutation occurred in the paternal transmissions, and the size increase was significantly smaller than in the maternal transmissions. This could partly explain the stability of the premutation through several generations in families with transmitting males. In the maternal transmissions, the risk of expansion of a premutation to a full mutation appeared to depend on its size. The critical maternal premutation size leading invariably to the full mutation was between = 175–200 bp. This is important for genetic counseling and also explains the commonly observed clustering of affected individuals in fragile X families. 相似文献
79.
Effects of kinetin,paclobutrazol and their interactions on the microtuberization of potato stem segments cultured in vitro in the light 总被引:1,自引:0,他引:1
I. Šimko 《Plant Growth Regulation》1993,12(1-2):23-27
Single-nodal cuttings of Solanum tuberosum (four cultivars) and Solanum chacoense were induced to produce in vitro microtubers on Murashige & Skoog (MS) medium supplemented with 8 g l–1 sucrose and various concentrations of kinetin and paclobutrazol. The cultures were kept 10 days in darkness and then transferred to a 14 h daylength with 100 µE m–2 sec–1 light intensity at 21 °C. Kinetin (2.5 mg l–1) had no significant influence on tuber formation. However, its addition together with paclobutrazol (0.001 mg l–1) significantly enhanced tuberization. Paclobutrazol alone stimulated early tuber initiation and inhibited stem growth. Despite some genotype × treatment interactions, all genotypes (from very early to late and wild type) formed the maximum proportion of explants bearing microtubers on the media containing both plant growth regulators. 相似文献
80.
Plot 82 is one of a hundred permanent plots that have been set up in Croatia for the purpose of long-term and continual investigations of ecosystems and their successions. It is located in the area of Karleuine Plase within the Plitvice Lakes National Park. Vegetation on the plot belongs to association Bromo-Plantaginetum mediae. The association develops in mountainous regions of continental Croatia within a wide altitude range, from 180–1300 m a.s.l. on shallow soil over pervious carbonate rocks. The floristic composition and phytocoenological characteristics of the association have been analyzed using the common methods of the phytocoenological school Zürich-Montpellier, on the basis of 17 phytocoenological records. In addition to floristic composition, some site characteristics have been analysed: soil moisture, calcium carbonate, phosphates, pH value, humus, cation exchange capacity and nitrogen mineralization on the site and in the laboratory. The results obtained are comparable with the data presented in the available phytocoenological and ecological literature. 相似文献